Engine stop-gear



D. COCKBURN AND n. MA'C'NICOLL.

ENGINE STOP GEAR. 'APPLICATION HLEVD mac. 9, 1919.

Patented 1161211921.

UNITED rariinr lortica.

DAVID COGKBURN AND DONALD MACNCOLL, OF CARDONALD, NEAR GLASGOW SCOTLAND.

ENG-INE STOP- GEAR.

i 1o all 't0/icm t may ccf/wem.

Be it known that We, DAVID Cocnnunn and DONALD MAcNiiooLL, subjects of the King et the United Kingdom of Great Britain and Ireland, and residing at (la-rdonald, nearV Glasgow, Scotland, have invented a certain. new and useful Improvement in Engine Stop-Gears, of' which the following is a specification.

This invention relates to engine stop gear in which a relay valve controls the iloiv of steam to a cylinder containing a piston operatively connected to an emergency valve which is closed on the opening of the relay valve, the relay valve being normally held closed by a piston movable in an oil-containing cylinder connected by piping to supply tank of a forcedl lubrication system.

Characteristic of the invention is the featurethat the tank has an overflow opening located above the level of the oil-containing cylinder and discharging into the piping connected to the said cylinder, from which piping there is a continuous escape into the return oil system, so that, as long as the cveridovv from the tank continues, the piston in the oilcontaining cylinder is maintained in position to close the relay valve, but when the overflow ceases the oil-containing cylinder is emptied and the piston therein falls so as to permit the relay valve to open.

In the drawings Figure l is a diagram partly in elevation partly in section showing an installation of engine stop gear according to the invention. F ig. 2 is a horizontal section showing the emergency valve.

In the construction illustrated there are tivo emergency valves and tivo relay valves. As the operation of one relay valve and its emergency valve is the same as that of the other relay valve and its emergency valve it Will be sufficient to describe only the operation of one relay valve and its emergency valve. It may be pointed out also that in the drawings, for the sake of clearness, the relay valves and emergency valves are shown to a much larger scale than the turbines the supply of steam to Which is controlled by the emergency valves.

The relay valve l is vertically movable by a piston 2 which is vertically movable in an oil-containing cylinder 3. The lovver side ot the piston 2 is acted on by oil led to the cylinder 3 by Way of an overilonT pipe connection 6 from an oil storage tank 4lat vbecil flowing into the pipe connection 6 at Specification of Letters Patent. Patented De@ 27 1921 Application led December 9, 1919.

Serial N0. 343,615.

a higher level than the cylinder 3. F rom a point near the upper end or" the cylinder 3 al a connection 5 for oil Which may leak past the piston 2. The piston 2 is held in V its highest position so long as the pipe conuecticn 6 is full of oil. The' pipe connection G has, however, a connection with a pipe 7 Jforming part of the return oil system of the turbine lll, so that oil isalways flowing from the pine connection 6. ln order, therefore, to maintain the piston 2 in its highest position, it is necessary that there should always llt a rate .not less than'the rate at which oil escapes from the pipe connection 6. Y

lllhen the level in the tank l falls below the overflow opening into the pipe connection 3 no further oil will enter the pipe connection 6, and as oil continues to escape into the pipe the dillerence in head between the tank el and the cylinder 3 becomes zero or a minus quantity. The piston 2 then falls under thef action of gravity and the relay valve l also ialls under the action of gravity. When the relay valve l is thus opening, steam is allowed to escape and the emergency valve 8 automatically closed by the steam. The flange ci the emergency valve is shown at 8X in Fig. l..

rllhe operation of the emergency valve is known per Se. When the relay valve lis open, steam from the face of the piston 9 nearest the valve 8 escapes by the port l() past the valve l and hence through the pipe ll. The pressure ot steam which has access to the other face of the piston 9 by Way of the pipe l2 and passage 13 now closes the valve 8.

The tank t supplies the turbines 14 With lubricant which flows continuouslythereto by Way of the pipe 18 and branches 18 to the turbines. So long as there is oil in the tank 4, the turbines are therefore supplied With lubricant.

A manually operable device 5 actuates 100 valves in the pipe connections 5, 6 so as to permit the discharge of oil from these pipes, when desired.

lt will be seen trom the oregoingthat the relay valve l depends for its operation 105 simply on the existence or absence of an overflow from the tank 4:.

l. In an engine stop gear, the combination with an emergency valve operable by fluid 110 pressure, a relay valve serving to control the escape of fluid pressure medium to eect operation ,of said emergency valve, a liquid conduit system, a cylinder connected to said system, a storage tank at a higher level than said cylinder, said tank having an overflow discharging into said system7 and a piston movable in said cylinder, said piston connected to said relay valve, one side of said piston exposed to the pressure due to the head of liquid between the point of overow from said tank land said cylinder, said piston maintaining said relay valve closed during the continuance of the overow but permitting said relay valve to open on cessation of the overflow. l

` 2; n an engine stop gear, the combination of an emergency valve, a fluid operated relay valve controlling the operation of the emergency valve, a storage tank for the fluid which voperates the relay valve having a ixed overflow level, the position of the sterage tank relative to the relay valve being such that when the liuid in the tank drops below the overow level the relay valve operates the emergency valve.

3. In an engine stop gear, the combination of an emergency valve, a relay valve controlling the operation of the emergency valve and operated yby the engine lubrication system, a storage tank for the lubricant having arxed overflow level, a connection between the storage tank and the relay valve, the position of the storage tank relative to the relay valve being such that when the lubricant in the tank drops below the overliow level the relayY valve operates the emergency valve.

Ll. Engine stop gear in which a relay valve controls the flow of steam to a cylinder eentaining a piston operatively connected to an emergency valve which is closed on the opening of the relay valve, the relay valveA being normally held'closed by a piston movable an oil-containing cylinder connected tion toclcse the relay valve, but when theV overflowceases the oil-containing cylinder is emptied and the piston therein falls so Y as te permit the relay valve to open.

in testimony whereof we have signed our Y names to this specification in the presence of two subscribing witnesses.

DAVD COCKBURN.

DONALD MACNICOLL. Y

litnesses: y Y y i KATE YOTHERNGHAN, c ISABEL ROLLO. 

